Industrial applications

Industrial applications and using the right grade of Radiolite and Topco filter aids

Both Radiolite diatomite ( Diatomaceous earth ) and Tepco perlite filter aids, are suitable for use in a variety of industries, and in different types of filtration systems. The filter aid of choice depends upon the customer’s specific operating conditions, and Showa offers Technical Support to the customers to optimize its filtration process.

As a rule of thumb when selecting candidate grades for testing, Radiolite R1100, R900S and R900 are suitable for filtration of suspensions with high viscosity and relatively large particulate; Radiolite R600 and R700 are suitable for filtration of general – purpose suspensions; and Radiolite R100, R200 and R300 are suitable for filtration of suspensions with low viscosity relatively small particle.

There are more than 20 different types of Radiolite – brand filter aids suitable for the effective diltration of almost any kinds of particulate. All are designed to take full advantage of the intrinsic properties of either marine or fresh-water origin diatomite over a wide range of grades from coarse to fine.

Choosing and using the right grade of Radiolite and Topco filter aids

Whether in batch-or continuous-filtration processes, the pre coat should always form a clean layer of uniform thickness. Pre coat should be applied using either a clear fluid or water and ideally pre coating is normally done at twice the filtration rate than actual filtration.

For pressure filters

2mm is a standard pre coat thickness, but the exact amount of Radiolite needed will vary depending upon the type of filter used and the grade of Radiolite selected for that particular application. As a rule of thumb, 0.5-1.5kg of Radiolite is need per square meter of filter area.

After verifying that application of the pre coat is complete, filtration of the suspension-and-body-feed mixture can begin.

The quantity of Radiolite needed for body feeding will depend entirely upon the quantity and quality of the particulate found in the suspension, so there are no established standard quantities. Thus, the optimal quantity for body feeding can only ve determined by empirical testing. In general, however, the volume of Radiolite should equal the volume of the total solids.

For Rotary vacuum pre coat filters

50-100mm is a standard ore coat thickness. In this case, as well, the use of body feeding is an effective means for promoting filtration and preventing particles from passing through the filter.

These are the general principles guiding the use of Radiolite filter aids.

In actual practice, however, adjustments must be made to accommodate factors filtration technique, physical characteristics of the suspension technique, physical characteristics of the suspension, and quantity of the most suitable grade and quantity of Radiolite for a given application is to laboratory testing, then make a final determination under actual usage conditions in the final field test.

Our central R&D Center in Tottori can conduct tests on customer’s process stream to assist in selecting the filter aid most suited, given each customer requirement We have a battery of laboratory test filters, some of which of our own design, which allows us to accurately predict operating conditions in an industrial environment.